"What's going to be key in New Zealand is being able to keep the tempo for 80 minutes and that's where we struggled against England in the second half," Gatland said.
"That was the whole reason for the game, to prepare to play a team like the All Blacks who keep going for the whole 80 minutes. I think we can be ready with more conditioning work in training and getting a little bit more accuracy in our attack."
After Wales traipsed off Twickenham, thumped 27-13, Gatland did his best to promote their trip to New Zealand, saying "there are no things we can't fix."
Many of the squad had not played a match of that standard for some time and there were issues around lineout security and the speed of their defensive line.
Statistics showed Wales missed 21 tackles and conceded 21 turnovers which will be even more worrying with captain Sam Warburton still on the mend from a shoulder problem and his deputy Dan Lydiate replaced at Twickenham with shoulder and hamstring damage and out of the tour.
Wales led by 10 points early, then lost by a wide margin as England scored five tries to one although George Ford missed four conversions and two penalties which would have turned it into a blowout.
